1. Technical Field
Various embodiments of the present disclosure relate to nonvolatile memory devices and methods of fabricating the same and, more particularly, to electrically programmable read only memory (EPROM) cells, EPROM cell arrays including the same, and methods of fabricating the same.
2. Related Art
EPROM devices may correspond to ROM devices that are electrically programmable. The EPROM devices belong to nonvolatile memory devices that retain their stored data even when their power supplies are interrupted. A unit cell of the EPROM devices may include a field effect transistor (FET) having a source region, a drain region, and a conductive channel region between the source region and the drain region. The FET used as the unit cell of the EPROM devices may have a floating gate disposed on the channel region. The floating gate of the EPROM cell may be electrically isolated. Electric charges may be injected into the floating gate of the EPROM cell to store information that is, a datum in the EPROM cell. Since the floating gate of the EPROM cell is electrically isolated, the electric charges injected into the floating gate of the EPROM cell may still remain even when a power supply of the EPROM device is interrupted. The electric charges injected into the floating gate of the EPROM cell may affect a conductivity of the channel region of the FET used as the EPROM cell. Thus, the information stored in the EPROM cell may be read out by detecting a current that flows through the channel region between the source region and the drain region.